package com.yc.resfoods.configs;

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.boot.web.context.WebServerInitializedEvent;
import org.springframework.context.ApplicationListener;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.util.ReflectionUtils;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
import org.springframework.web.servlet.mvc.method.RequestMappingInfoHandlerMapping;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.oas.annotations.EnableOpenApi;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.spring.web.plugins.WebFluxRequestHandlerProvider;
import springfox.documentation.spring.web.plugins.WebMvcRequestHandlerProvider;

import java.lang.reflect.Field;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @ClassName SwaggerConfig
 * @since: 2023/8/20 16:02
 * @auth: kirito
 * @description:
 **/
@Configuration
@EnableOpenApi
@Slf4j
public class SwaggerConfig implements ApplicationListener<WebServerInitializedEvent> {
    @Bean
    public Docket createRestApi(){
        return new Docket(DocumentationType.OAS_30)
                .apiInfo(getApiInfo())
                .groupName("SwaggerGroupOneAPI")
                .select()
                .apis(RequestHandlerSelectors.withClassAnnotation(RestController.class))
                .paths(PathSelectors.any())
                .build();
    }

    public ApiInfo getApiInfo(){
        return new ApiInfoBuilder()
                .title("小萌神应用平台") // 文档标题
                .description("小萌神应用平台文档描述") // 文档描述
                .termsOfServiceUrl("http://www.baidu.com")
                .version("1.0")
                .build();

    }

    /**
     * 解决SpringBoot和Swagger2冲突
     *
     * @return
     */
    @Bean
    public static BeanPostProcessor springfoxHandlerProviderBeanPostProcessor() {
        return new BeanPostProcessor() {

            @Override
            public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
                if (bean instanceof WebMvcRequestHandlerProvider || bean instanceof WebFluxRequestHandlerProvider) {
                    customizeSpringfoxHandlerMappings(getHandlerMappings(bean));
                }
                return bean;
            }

            private <T extends RequestMappingInfoHandlerMapping> void customizeSpringfoxHandlerMappings(List<T> mappings) {
                List<T> copy = mappings.stream()
                        .filter(mapping -> mapping.getPatternParser() == null)
                        .collect(Collectors.toList());
                mappings.clear();
                mappings.addAll(copy);
            }

            @SuppressWarnings("unchecked")
            private List<RequestMappingInfoHandlerMapping> getHandlerMappings(Object bean) {
                try {
                    Field field = ReflectionUtils.findField(bean.getClass(), "handlerMappings");
                    field.setAccessible(true);
                    return (List<RequestMappingInfoHandlerMapping>) field.get(bean);
                } catch (IllegalArgumentException | IllegalAccessException e) {
                    log.warn("修改WebMvcRequestHandlerProvider的属性：handlerMappings出错，可能导致swagger不可用", e);
                    throw new IllegalStateException(e);
                }
            }
        };
    }

    @Override
    public void onApplicationEvent(WebServerInitializedEvent event) {

    }
}